Cups and cones and the like



Jan. 9, 1923. V ,441,892;

H. H. TIMKEN. MANUFACTURE OF ROLLER BEARING 'cuPs AND CONES AND THE LIKE.

' HLED JAN. 10. I92]. 2 SHEETS-SHEET 1..

yum! B Jan. 9, 1923. 1,441,892. H. H. TIMKEN. MANUFACTURE or ROLLER BEARING CUPS AND CONES AND THE UKE.

FILED lAN.1d, I92!- 2 SHEETS-SHE 2' I [I 2 i H n I 5 H: {5 I I 0 W IIHII HIIHI Patented Jan. 9, 1923.

UNITED sTA'rEs PATENT OFFICE.

HENRY H, .TIMKEN, OF CANTON, OHIO, ASSIGNOR TO THE TIE/[KEN ROLLER BEARING COMPANY, OF CANTON, OHIO, A CORPORATION OF OHIO.

MANUFACTURE OF ROLLER-BEARING CUPS AND (JONES AND THE LIKE.

Application filed January 10, 1921. Serial No. 436,267.

To all? whom it may concern:

Be it known that I, HENRY l-l. TIMKEN, a citizen of the United States, and a resident of the city of Canton, in the county of. Stark and State of Ohio, have invented a new and useful Improvement in the Manufacture of Roller-Bearing Cups and Cones and the like,'of which the following is a specification.

The process of manufacturing metal rings, such as cups and c'ones for roller bearings, now commonly practiced, comprises the use of cutting tools to bring the stool; to approximately the size and shape desired for the finished article, after which the green rings are usually submitted to heat treatment and then ground and finished. On account of the high degree of precision required in such articles, and the high percentage of loss in heat treatment and grinding, this common process is necessarily expensive; besides, it is liable to produce in juries to the article which are not readily detectable at first but which develop in use and impair the value of the bearing of which such article is a part. It is the principal object of the present invention to obtain results superior to the results of the old process and at a great reduction of cost.

The invention consists principally in converting the stock, by any suitable process, into approximately the form and shape de sired for the finished article, then obliterating the irregularities of the surface or surfaces of the green article by suitable pressure thereon; after which the green article will ordinarily be heat treated and quenched in a sizing and shaping device. The term green article, as used herein, is intended to denote the stage of manufacture prior to hardening by heat treatment. The invention is further disclosed in the following specification.

In the accompanying drawing, which forms part of this specification, and wherein like reference numerals refer to like parts whereever they occur,

Fig. 1 is a vertical section of mechanism suitable for rolling the end and inner surface of a cup inconformity with my in vention;

Fig. 2 is a plan view of the mechanism shown in Fig. 1 with the shank holder removed Fig. 3 is a plan view of the device for holding rolls which engage the interior surface of the cup;

Fig. 4 is a side elevation, partly sectional, of a device fortruing the outer surface of the cup concentric with the inner; and

Fig. 5 is a plan view thereof with the rolling head and cup shown in section.

in order to be satisfactory for use, cups and cones for roller bearings must not only be unvarying and accurate in shape and size, but must also have sound and very smooth surfaces. The grinding of such articles produces irregulaties of surface and variations in form from that desired, andis liable to damage the surface portion of the metal. Consequently the process now commonly practiced does not produce as smooth and sound a surface and as accurate a form as is desirable for articles such bearing members. My present invention produces an article of a very smooth and glassy surface and of great accuracy of form without grinding and without impairing any portion of the metal.

The present process is especially adapted to the manufacture of steel rings and be gins with the formation, in any suitable manner, of a green article of approximately the size and shape of the finished article. For instance, assume that it is desired to produce a cup for a conical roller bearing: the initial stock, which is of comparatively soft steel, may be cut, forged or otherwise formed into a green cup of approximately the size and shape of the finished article but with its inner or bearing surface left without a high degree of finish and with allowances in the diameter and taper of the bore for subsequent operations. as herein after mentioned. The metal of this green cup is sufliciently soft and plastic even when coldto flow under a sufficiently high degree of pressure, that is to say, a pressure in ex cess of the elastic limit of the metal. On the other hand, if the pressure exceeds the limit of plasticity of the metal, the metal will be ruptured and the cup rendered unfit for use. Accordingly the bearing surface of the green cup is submitted to pres sure in excess of the elastic limit of the metal, but below the limit of plasticity thereof. In this way, the bearing surface is smoothed and given a high degree of finish Without impairing the soundness of the metal and the green cup is given the form desired therefor, as hereinafter set forth. When the green cup is to behardened, as is usually the case, a slight allowmice is made therefor in the size and taper of the green cup, as hereinafter set forth.

In car "ying out the process with the aid of the device illustrated in the accompanying drawing, the green cup A is placed on the back face rolls B, which are free to roll in and on the bed plate F, and is submitted to pressure by means of finished rolls K, which are journaled in pockets P provided therefor in the outer periphery of the cone M and Worked downwardly and outwardly against the inner surface thereof. The revolving spindle L and cone M thereof .in conjunction with the downward axial pressure on the spindle (which downward and revolving motion of the spindle is produced by any suitable device such as a drill press having a holder H adapted to receive said spindle) cause the cup to revolve on the rolls and the rolls K, which rolls, in turn, turn in their seats and travel cireumferentially with the cups. This action on the back face of the one makes the same smooth, plane and sound. This result is obtained normally in a very short time and then a brake such as the band brake C l-G shown inFigs. l and 2 is applied and the cup is thereby held against further rotation, but the rotation and downward axial pressure of the spindle L, cone M and rolls K. continues.

In a short time this above described action of the rolls K under pressure working against the inner surface of the cup produces a smooth, circular and sound inner surface thereon. This pressure may be applied to a green cup with rolls mounted thereon similar to the relation of the rollers of a finished bearing to the cup thereof. This pressure may be applied by one or more rolls and the diameter of the rolls used may be as great as the space available for operation in the cup under treatment. The green cup is seated in axial alinement with the longitudinally moving plunger ll of a press, the cone M of this plunger being rotatable about the axis thereof and being provided with circular series of rolls K whose axes lie in a cone with its apex in the axis of the plunger. Thus the rollers and work have the same velocity at their lines of contact and the pressure is applied radially and without any tendency to abrade or tear the metal, such as is chacteristic of grinding operations and such as might result from rubbing under pressure. By this arrangement the rolling operation performs its work gradually and thus allows the metal to accommodate itself to the best advantage in accordance with the laws of plastic flow. It is noted tha in this process no one roller does any considerable amount of work at any one time but each roller continues after a very slight intermission the work of the roller preceding it; and with the multiplicity of revolutions of the conical plunger head, and the increase of pressure due to the advance of the plunger, a Very smooth surface is obtained without damage to the metal thereof and with the desired readjustalinement with a revolving member, such as an arbor D and locked by a suitable device, as, for example, a washer E and nut N.

A cutting tool 0 suitably mounted, as, for instance, in a rest TV, travels across the outside surface of the cup after the manner of a lathe tool to true the outer surface thereof, usually to a cylindrical form, concentric with the inner surface, and immediately the spaced rolls Q of a roller head S, which is plvotally mounted on the stud T of a roller head yoke Y, exert pressure on thissurface, smoothing and sizing the same without damage to the material. Thus the threei'mportant surfaces ack face, inside surface and outside surface) are produced with superior, accurate and true surfaces without damage to the metal. When such cup is hardened unc expansion and restraint, its surfaces excel the results obtained by grinding. I

Ordinarily, it is desirable to harden or case-harden and harden the green cup with the very smooth surface just mentioned and then submit the same to suitable heat treatmentand then to mount 'it on a plug of substantially the size and taper required for the inner surface of the finished cup and to quench it on said plug, 'llhis plug is intended to actually stretch the hot green cup circumferentially throughout the length of the cup with the double purpose of sizing and shaping the same by flowing the metal and of generating a considerable circumferential stress that will prevent distortion during and after quenching and assure the preservation of the finish of the surface of he cup. The cup is thenstripped from the plug and is in condition for use \vithout fur ther treatment of its inner or hearing surface. A. sui ble process for such qulibhiug operation, if one is desired, is disclosed in Lothrop application Serial No. 367,897, filed March 22, 1920.

Owing to the elasticity of the metal, the cup will change shape very slightly when it is stripped from the plug on which it is hardened, the thicker end of the cup shrinking to a smaller diameter and the taper of the bore increasing. The amount of this change is constant for given conditionsof size, shape and material of the cup and is ascertainable by trial and is taken into account in determining the size and taper of the plug and the angular position of the smoothing rolls, so that, when the cup is cool, it will be of the desired size and shape. As suggested above, the amount of change varieswith the material and may be negligible in the case of certain alloys that shrink very slightly in quenching- It is noted-that the present process is characterized largely by causing a plastic'fiow of the surface portion of the metal. of the green cup under conditions which produce smooth surfaces of the size and form required followed ordinarily by a hardening treatment under conditions which will prevent appreciable distortion of the bearing surface but involving no operation which will impair the integrity of the metal.

Instead of the pressure being applied by means of a roll or rolls,-the surface of the cup may be smoothed and the green cup given the form and size desired therefor, by submitting it, while held on a suitable seat or in-a die, to the action of a plug axially movable relativel thereto and whose surface is highly finished and hardened and is of the form desired to give the proper form and size to the inner surface of the green cup. The action of the movable plug :is similar to that above described, that is, the high and low regions are evened up without impairing the metal, so that the inner surface of the cup is smoothed and given a high degree of finish.

It is feasible to produce the smooth surface and desired form of the cup by any suitable rolling or rubbing tool orimplement that exerts sufiicient pressure to overcome the elasticity of the metal without e2:- ceeding the limit of plasticity thereof. So, too, the work may move while the tool or implement remains stationary.

The process is applicable to the manufacture of other articles than roller bearing cups; for instance, it may be used in the manufacture of bearing cones or bearing rollers or of other metal rings.

Among the advantages of the above de scribed process, as compared with previous processes, are that it does not call for the same high degree pf accuracy in making the green cups and cones, it greatly reduces the expense of inspection," it dispenses with the expensive operation of grinding with the losses and imperfections of the product incidental thereto, and it reduces to a minimum the losses due to the scrapping of imperfect products. Another great advantage is that it enables a plurality of operations to be effected simultaneously or without resetting tools or work and therefore assures the greatest precision in the relation of the several surfaces, including not only the inner and outer surfaces but the end surfaces also; this advantage is of very great importance in obtaining perfect concentricity for the inner and outer surfaces and proper finish and angularity for the back faces, and, in the case of ribbed cones, assuring the correct position thereof. Another advantage is that the smoothing pressure may be applied by tools mounted on the same machine that makes the green article, and therefore without'risk of improper centering of the article, and at a greatly reduced cost. It is also noted. that the use of rollers eliminates the necessity for frequent redressing and replacement incidental to the use of cutting tools.

Another advantage is, that as my inven tion enables articles to be produced with highly finished surfaces and accurate shapes and sizes without grinding after the articles are hardened, therefore, the distortion that occurs after a hardened surface is ground is eliminated and the permanency of shape and form is retained.

While my invention produces articles which do not require grinding, or other op eration to make them usable, there may be cases of inferior products which may be saved by slight grinding.

Obviously, my invention is applicable to the production of other articles than those above mentioned and also admits of considerable variations in detail, and therefore I do not wish to be limited to the specific de tails set forth.

What I claim is:

1. The process of making roller bearing cups and cones and the like which consists in making a green article of approximately the size and shape of the linishedarticle and smoothinga surface of said article by pressure in excess of its limit of elasticity but less than its limit of plasticity so as to effect a permanent flow of the surface portion that is immediately subjected to pressure without effecting appreciable elongation of the article, heat treating said green article, and

then quenching the same.

2. The process of making roller bearing cups and cones and the like which consists in making a green article of approximately the size and shape of the finished article and smoothing a surface of said article by pressure in excess of its limit of elasticity but less than its limit of plasticity so as to effect a flow of the surface portion that is immediately subjected to pressure without effecting appreciable elongation of the artitcle, heat treating said green article and then quenching the same under restraint to prevent distortion.

3. The process of making roller bearing cups and the like which comprises making a green article, smoothing the bearing surfacethereof by pressure in excess of the limit of elasticity of the metal but less than its limit of plasticity, of approximately the shape but of slightly smaller bore than the finished article, heat treating said green article, expanding the same with a plug of slightly greater size but less taper than the bore of the finished article, and quenching the same while under expansion on said plug.

The process of making roller bearing cups and the like which comprises making a green article, smoothing the bearing surface thereof by pressure in excess of the limit of elasticity of the metal but less than its limit of plasticity of approxim ately the shape but of slightly smaller size and less taper 0t here than the finished article, heat treating said green article, expanding the same with a plug of slightly greater size but less taper than the bore of the finished article, and quenching the same while under expansion on said plug.

5. The process of making roller bearing cones and the like which comprises making a green article, smoothing the bearing surface thereof by pressure in excess of the limit of the elasticity of the metal but less than its limit of plasticity, of approximately the shape but of slightly smaller bore than the finished article, heat treating said green article, expanding the same with a plug of slightly greater size than the bore of the finished article and quenching the same vhile under expansion on said plug.

6. The process of making roller bearing cups and cones and the like which comprises the making of a green article, smoothing the bearing surface thereof to approximately the size and shape of the finished article, and with a smaller bore than the finished article, heat treating said article, expanding the heated article mechanically and quenching the same while mechanically restrained, such smoothing being effected by radial pressure insufficient to cause substantial elongation of the article.

7. The process of making roller bearing cups and cones and the like which comprises the making of a green article, smoothlng the bearing surface thereof to approximately the size and shape but of smaller and less tapered bore than the finished article, heat treating said article, expanding the heated article mechanically and quenching the same while mechanically rest-rained.

8. The process of making roller bearing cups and cones and the like which comprises the making of a green article with a bore of a slightly less diameter than is desired for the finished article, smoothing the bearing surface of said article, heat treating said article, enlarging the bore of the heated article with a plug of slightly larger diameter than desired for the bore of the finished article, and quenching the said article wl he in expanded condition on said plug.

9. The process of making roller bearing cups and cones and the like which comprises he making a green article with a bore of lightly less diameter and slightly l taper ban is desired for the finished article, smoothing the hearing sr of said article, heat treating said artwie, enlarging the bore of the heated article with a tapered plug of slightly larger diameter but less per than desired for the bore of the finished article, and quenching said article while in expanded condition on said plug.

10. The process of n'ia-king roller bearing cups and cones and the like which comprises making a green article of approximately the size and shape of the finished article, and

smoothing a surface of said article by applying pressure on its circumference, such pressure being sutficient to ellect a plastic flow of the metal for only a limited depth opposite the place where the pressure is applied.

11. The process of making roller bearing cups and cones and the like which comprises making a green article of approximately the size and shape of the finished article, and smoothing a surface of said article without removing any of the material thereof by applying pressure on its circumference thereof, such pressure being sufficientto effect a plastic flow of the metal for only a limited depth opposite the place where the pressure is applied.

12. The process of making roller bearing cups and cones and the like which comprises making a green article of approximately the and shape of the finished article and smoothing a surface of said article by pressure in excess of its limit of elasticity but less than its limit of plasticitywhereby appreciable elongation is avoided.

13. The process of making roller bearing cups and cones and the like which consists in making a green article of approximately the size and shape of the finished article, smoothing a surface of said article by radial pressure sufficient to permanently merge the elevated portions immediately exposed to the pressure into the mass without appreciable upsetting of the metal, carburizing said article, heating the same, and quenching the same under restraint to prevent distortion.

14. The process of making roller bearing cups and cones and the like which consists in making a green article of approximately the size and shape of the finished article, smoothing a surface of said article by pressure applied radially to the wall thereof sufficient to flow the elevated portions to which the pressure is applied but insulticient to disturb the deeper portions of the wall case hardening said article, heating the same, and then quenching the same.

15. The process of making roller bearing cups and cones and the like Which comprises the making of a green article, smoothing the bearing surface thereof to approximately the size and shape of the finished article and with smaller bore than the finished article, carburizing said article, heating said article and expanding the same mechanically, and quenching the heated and expanded article While mechanically restrained against shrinking, the smoothing pressure being sufiicient to permanently flow the elevated surface portions of the metal Without appreciable elongation of the article.

16. The process of making roller bearing cups and cones and the like which consists in making a green article of approximately the size and shape of the finished article, smoothing a surface of said article by applying radial pressure progressively around its circumference While the other surface is under restraint carburizing said article, heat treating said green article, and then quenching the same under restraint to prevent distortion, the smoothing pressure being suflicient to permanently flow the elevated surface portions of the metal Without appreciable elongation of the article.

17. The process of making roller bearing cups and cones and the like which consists in making a green article of approximately the size and shape of the finished article, rolling a surface of said article With pressure suflicient to merge the elevated portions immediately exposed to the pressure into the mass of metal Without appreciable disturbance of the deeper portions of the section and hardening said article.

I 18. The process of making roller bearing cups and cones and the like which comprises the making of a green article and smooth.- ing the bearing surface and back face there of simultaneously, such smoothing being effected by radial pressure suflicient to permanently merge the elevated portions into the mass of metal Without appreciable upsetting.

19. The process of making roller bearing cups and cones and the like Which comprises the making of a green article and smoothing the bearing surface and back face thereof Without resetting the article, such smoothing being efiected by radial pressure sufficient to permanently merge the elevated portions into the mass of metal Without ap preciable upsetting.

20. The process of making roller bearing cups and cones and the like which comprises the making of a green article and smoothing a plurality of surfaces thereof simultaneously, such smoothing being effected by radial pressure sufficient to permanently merge the elevated portions into the mass of metal Without appreciable upsetting.

21. The process of making roller bearing cones which comprises the making of a green cone and smoothing a plurality of surfaces thereof Without resetting the article, such smoothing being effected by radial pressure sufficient to permanently merge the elevated portions into the mass of metal Without appreciable u setting.

Signed at Canton, hio, this 4th day of January, 1921.

HENRY H. TIMKEN. 

